merged in zeroflow's fixes and my related changes:
- fixed main emitters coming on while changing aux LED mode
- made strobe group mode selection more configurable at compile time
- refactored eeprom indexes in the same manner as strobe indexes,
for cleaner and more robust code
- added -fshort-enums to compile options for smaller ROM size
- made interrupt_nice_delays() automatic every time the user completes
a button press sequence, so all delays collapse until the next trip
through main()... this reduces ROM size and simplifies code and
eliminates risk of not responding right away